How long could you survive in a coffin?

Question

After watching Kill Bill 2 last night, I want to know: How long would you survive buried underground in a coffin?Michael, Ealing

Answer

** Definitive **Name: Oliver, HaringeyQualification: I saw it on MythbustersAnswer: The answer is 45 minutes. They did an experiment with a coffin with perpex sides so you could see in and that was the result.